STOCK TITAN

Ultragenyx (RARE) CFO trims stake with 4,683-share open-market sale

Filing Impact
(High)
Filing Sentiment
(Negative)
Form Type
4

Rhea-AI Filing Summary

Ultragenyx Pharmaceutical Inc.’s Chief Financial Officer Howard Horn reported an open-market sale of 4,683 shares of common stock at $24.90 per share. After this transaction, he directly owns 110,342 shares, which the disclosure notes include shares underlying RSUs that are subject to vesting conditions.

Positive

  • None.

Negative

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Insider Horn Howard
Role Chief Financial Officer
Sold 4,683 shs ($117K)
Type Security Shares Price Value
Sale Common Stock 4,683 $24.90 $117K
Holdings After Transaction: Common Stock — 110,342 shares (Direct, null)
Footnotes (1)
  1. [object Object]
Shares sold 4,683 shares Common stock sold in open-market transaction
Sale price $24.90 per share Price for the 4,683 common shares sold
Post-transaction holdings 110,342 shares Directly owned after sale, including RSU underlying shares
open-market sale financial
"transaction_action": "open-market sale""
An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.
RSUs financial
"shares of common stock underlying RSUs granted to the Reporting Person"
RSUs, or restricted stock units, are a form of company shares given to employees as part of their compensation. They are typically awarded with certain restrictions, such as a waiting period before they can be fully owned or sold, similar to earning a gift that becomes fully yours over time. For investors, RSUs can impact a company's stock offerings and reflect how much the company relies on stock-based incentives to attract and retain talent.
vesting conditions financial
"RSUs granted to the Reporting Person, which are subject to certain vesting conditions"
Vesting conditions are the rules that determine when someone earning company stock or stock options actually gains the right to keep or sell them, typically based on staying with the company for a set time or meeting performance targets. Think of it like keys that unlock gradually — some unlock by calendar date, others only after agreed milestones. Investors care because vesting shapes management incentives, the timing of share sales, and the number of shares that can enter the market, which can affect a company's valuation and ownership mix.
non-derivative financial
""transaction_type": "non-derivative""
SEC Form 4
FORM 4UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number:3235-0287
Estimated average burden
hours per response:0.5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
X
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
1. Name and Address of Reporting Person*
Horn Howard

(Last)(First)(Middle)
C/O ULTRAGENYX PHARMACEUTICAL INC.
60 LEVERONI COURT

(Street)
NOVATO CALIFORNIA 94949

(City)(State)(Zip)

UNITED STATES

(Country)
2. Issuer Name and Ticker or Trading Symbol
Ultragenyx Pharmaceutical Inc. [ RARE ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
Director10% Owner
XOfficer (give title below)Other (specify below)
Chief Financial Officer
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
05/01/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
XForm filed by One Reporting Person
Form filed by More than One Reporting Person
4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year)2A. Deemed Execution Date, if any (Month/Day/Year)3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeVAmount(A) or (D)Price
Common Stock05/01/2026S4,683D$24.9110,342(1)D
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year)3A. Deemed Execution Date, if any (Month/Day/Year)4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 6. Date Exercisable and Expiration Date (Month/Day/Year)7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
Explanation of Responses:
1. Includes previously reported shares of common stock underlying RSUs granted to the Reporting Person, which are subject to certain vesting conditions.
/s/ Karah Parschauer, attorney-in-fact05/04/2026
** Signature of Reporting PersonDate
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did Ultragenyx (RARE) disclose in this Form 4?

Ultragenyx disclosed that Chief Financial Officer Howard Horn completed an open-market sale of company common stock. The filing reports a single transaction in which he sold 4,683 shares, providing details on the sale price and his direct share ownership after the transaction.

How many Ultragenyx (RARE) shares did CFO Howard Horn sell?

Howard Horn sold 4,683 shares of Ultragenyx common stock. This sale was reported as a non-derivative transaction on the Form 4 and categorized as an open-market or private transaction, giving investors visibility into a specific reduction in his directly held share position.

At what price were the Ultragenyx (RARE) shares sold by the CFO?

The shares were sold at $24.90 per share. This reported sale price reflects the average transaction price for the 4,683 common shares sold in the open market, as disclosed in the Form 4, and is used to calculate the total value of the disposition.

How many Ultragenyx (RARE) shares does CFO Howard Horn hold after the sale?

After the transaction, Howard Horn directly holds 110,342 Ultragenyx shares. The filing indicates this post-transaction ownership figure, helping investors understand his continuing equity stake in the company following the reported open-market sale of 4,683 common shares.

Do the CFO’s reported Ultragenyx (RARE) holdings include RSUs?

Yes. A footnote explains that the reported holdings include previously reported shares underlying RSUs granted to Howard Horn. These restricted stock units are subject to vesting conditions, meaning some of the reported shares represent awards that vest over time rather than already fully unrestricted stock.